This formulation adds in momentum, or p, and also multiplies it by the speed of light. Written out, the equation is: E^2=p^2c^2 + m^2c^4. In the case of a photon, for which m=0, the equation boils ...

The flow is from bottom to top. The Reynolds number based on momentum thickness at the midpoint of the volume is 700. A passive scalar has been introduced into the flow along a spanwise line at the ...